xref: /openbmc/linux/drivers/ata/pata_opti.c (revision afb46f79)
1 /*
2  * pata_opti.c 	- ATI PATA for new ATA layer
3  *			  (C) 2005 Red Hat Inc
4  *
5  * Based on
6  *  linux/drivers/ide/pci/opti621.c		Version 0.7	Sept 10, 2002
7  *
8  *  Copyright (C) 1996-1998  Linus Torvalds & authors (see below)
9  *
10  * Authors:
11  * Jaromir Koutek <miri@punknet.cz>,
12  * Jan Harkes <jaharkes@cwi.nl>,
13  * Mark Lord <mlord@pobox.com>
14  * Some parts of code are from ali14xx.c and from rz1000.c.
15  *
16  * Also consulted the FreeBSD prototype driver by Kevin Day to try
17  * and resolve some confusions. Further documentation can be found in
18  * Ralf Brown's interrupt list
19  *
20  * If you have other variants of the Opti range (Viper/Vendetta) please
21  * try this driver with those PCI idents and report back. For the later
22  * chips see the pata_optidma driver
23  *
24  */
25 
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/pci.h>
29 #include <linux/blkdev.h>
30 #include <linux/delay.h>
31 #include <scsi/scsi_host.h>
32 #include <linux/libata.h>
33 
34 #define DRV_NAME "pata_opti"
35 #define DRV_VERSION "0.2.9"
36 
37 enum {
38 	READ_REG	= 0,	/* index of Read cycle timing register */
39 	WRITE_REG 	= 1,	/* index of Write cycle timing register */
40 	CNTRL_REG 	= 3,	/* index of Control register */
41 	STRAP_REG 	= 5,	/* index of Strap register */
42 	MISC_REG 	= 6	/* index of Miscellaneous register */
43 };
44 
45 /**
46  *	opti_pre_reset		-	probe begin
47  *	@link: ATA link
48  *	@deadline: deadline jiffies for the operation
49  *
50  *	Set up cable type and use generic probe init
51  */
52 
53 static int opti_pre_reset(struct ata_link *link, unsigned long deadline)
54 {
55 	struct ata_port *ap = link->ap;
56 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
57 	static const struct pci_bits opti_enable_bits[] = {
58 		{ 0x45, 1, 0x80, 0x00 },
59 		{ 0x40, 1, 0x08, 0x00 }
60 	};
61 
62 	if (!pci_test_config_bits(pdev, &opti_enable_bits[ap->port_no]))
63 		return -ENOENT;
64 
65 	return ata_sff_prereset(link, deadline);
66 }
67 
68 /**
69  *	opti_write_reg		-	control register setup
70  *	@ap: ATA port
71  *	@value: value
72  *	@reg: control register number
73  *
74  *	The Opti uses magic 'trapdoor' register accesses to do configuration
75  *	rather than using PCI space as other controllers do. The double inw
76  *	on the error register activates configuration mode. We can then write
77  *	the control register
78  */
79 
80 static void opti_write_reg(struct ata_port *ap, u8 val, int reg)
81 {
82 	void __iomem *regio = ap->ioaddr.cmd_addr;
83 
84 	/* These 3 unlock the control register access */
85 	ioread16(regio + 1);
86 	ioread16(regio + 1);
87 	iowrite8(3, regio + 2);
88 
89 	/* Do the I/O */
90 	iowrite8(val, regio + reg);
91 
92 	/* Relock */
93 	iowrite8(0x83, regio + 2);
94 }
95 
96 /**
97  *	opti_set_piomode	-	set initial PIO mode data
98  *	@ap: ATA interface
99  *	@adev: ATA device
100  *
101  *	Called to do the PIO mode setup. Timing numbers are taken from
102  *	the FreeBSD driver then pre computed to keep the code clean. There
103  *	are two tables depending on the hardware clock speed.
104  */
105 
106 static void opti_set_piomode(struct ata_port *ap, struct ata_device *adev)
107 {
108 	struct ata_device *pair = ata_dev_pair(adev);
109 	int clock;
110 	int pio = adev->pio_mode - XFER_PIO_0;
111 	void __iomem *regio = ap->ioaddr.cmd_addr;
112 	u8 addr;
113 
114 	/* Address table precomputed with prefetch off and a DCLK of 2 */
115 	static const u8 addr_timing[2][5] = {
116 		{ 0x30, 0x20, 0x20, 0x10, 0x10 },
117 		{ 0x20, 0x20, 0x10, 0x10, 0x10 }
118 	};
119 	static const u8 data_rec_timing[2][5] = {
120 		{ 0x6B, 0x56, 0x42, 0x32, 0x31 },
121 		{ 0x58, 0x44, 0x32, 0x22, 0x21 }
122 	};
123 
124 	iowrite8(0xff, regio + 5);
125 	clock = ioread16(regio + 5) & 1;
126 
127 	/*
128  	 *	As with many controllers the address setup time is shared
129  	 *	and must suit both devices if present.
130 	 */
131 
132 	addr = addr_timing[clock][pio];
133 	if (pair) {
134 		/* Hardware constraint */
135 		u8 pair_addr = addr_timing[clock][pair->pio_mode - XFER_PIO_0];
136 		if (pair_addr > addr)
137 			addr = pair_addr;
138 	}
139 
140 	/* Commence primary programming sequence */
141 	opti_write_reg(ap, adev->devno, MISC_REG);
142 	opti_write_reg(ap, data_rec_timing[clock][pio], READ_REG);
143 	opti_write_reg(ap, data_rec_timing[clock][pio], WRITE_REG);
144 	opti_write_reg(ap, addr, MISC_REG);
145 
146 	/* Programming sequence complete, override strapping */
147 	opti_write_reg(ap, 0x85, CNTRL_REG);
148 }
149 
150 static struct scsi_host_template opti_sht = {
151 	ATA_PIO_SHT(DRV_NAME),
152 };
153 
154 static struct ata_port_operations opti_port_ops = {
155 	.inherits	= &ata_sff_port_ops,
156 	.cable_detect	= ata_cable_40wire,
157 	.set_piomode	= opti_set_piomode,
158 	.prereset	= opti_pre_reset,
159 };
160 
161 static int opti_init_one(struct pci_dev *dev, const struct pci_device_id *id)
162 {
163 	static const struct ata_port_info info = {
164 		.flags = ATA_FLAG_SLAVE_POSS,
165 		.pio_mask = ATA_PIO4,
166 		.port_ops = &opti_port_ops
167 	};
168 	const struct ata_port_info *ppi[] = { &info, NULL };
169 
170 	ata_print_version_once(&dev->dev, DRV_VERSION);
171 
172 	return ata_pci_sff_init_one(dev, ppi, &opti_sht, NULL, 0);
173 }
174 
175 static const struct pci_device_id opti[] = {
176 	{ PCI_VDEVICE(OPTI, PCI_DEVICE_ID_OPTI_82C621), 0 },
177 	{ PCI_VDEVICE(OPTI, PCI_DEVICE_ID_OPTI_82C825), 1 },
178 
179 	{ },
180 };
181 
182 static struct pci_driver opti_pci_driver = {
183 	.name 		= DRV_NAME,
184 	.id_table	= opti,
185 	.probe 		= opti_init_one,
186 	.remove		= ata_pci_remove_one,
187 #ifdef CONFIG_PM
188 	.suspend	= ata_pci_device_suspend,
189 	.resume		= ata_pci_device_resume,
190 #endif
191 };
192 
193 module_pci_driver(opti_pci_driver);
194 
195 MODULE_AUTHOR("Alan Cox");
196 MODULE_DESCRIPTION("low-level driver for Opti 621/621X");
197 MODULE_LICENSE("GPL");
198 MODULE_DEVICE_TABLE(pci, opti);
199 MODULE_VERSION(DRV_VERSION);
200